Interphase detection of trisomy 12 in B-cell chronic lymphocytic leukemia by fluorescence hybridization in situ

Fluorescence hybridization in situ with a probe specific for the alphoid sequence of the centromeric region of chromosome 12 was used to evaluate seven cases of B-cell chronic lymphocytic leukemia (B-CLL). Trisomy 12 was detected in interphase cells from one case which did not produce analyzable metaphases. Four out of the seven cases studied showed clear evidence of trisomy 12 in interphase nuclei. In situ hybridization provides an important supplement to classic cytogenetic studies of B-CLL and may help refine our understanding of the clinical correlations of chromosome abnormalities.